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Friday, September 04, 2009

Hidden in the woods about 10 km southeast of Frankfurt International Airport is GSI, the Helmholtz Centre for Heavy Ion Research. GSI is an accelerator laboratory for research with beams of all kinds of ions up to uranium. It is best known for its discoveries of new elements, such as Copernicium, and for exploration of the use of beams of carbon ions in tumor therapy. But there is also research done in heavy ion collisions to study properties of nuclear matter, in plasma physics, and atomic physics, where heavy ions allow to probe quantum electrodynamics in strong electromagnetic fields.

In the upcoming years, GSI will expand enormously, through the construction of FAIR, the Facility for Antiproton and Ion Research.

A plan of GSI, and the new FAIR complex, shown in red. From the flyer "FAIR: Facility for Antiproton and Ion Research" (PDF file).FAIR is a large international project, with a billion-euro budget. It will consist of several accelerators and storage rings, and provide high-intensity beams of heavy ions and antiprotons, and secondary beams of rare and unstable nuclei. Many different experiments will study phenomena as diverse as compressed baryonic matter, nuclear structure relevant for astrophysics, antiproton-proton collisions for hadron spectroscopy, or properties of high-energy irradiation for biophysics and materials research.

Construction of the FAIR accelerators has not begun yet, but yesterday saw the topping-out ceremony of the first hall built, the testing hall, where parts of the accelerators, bending magnets and experimental equipment will be thoroughly checked before deployment in the facility.

The topping-out, or "Richtfest," is a quite typical German tradition: Once the raw structure of a building up to the roof has been erected, a ceremony and subsequent party with the building owner, the architects, and the craftsmen is held. It's an occasion for a few solemn speeches, an occasion for politicians to pose for photos, and for exchanging best wishes for the future of the project.

As we were in the area yesterday, we used the opportunity to attend the topping-out, and to say hello to some old friends. Let's also not forget that following the ceremony there was the annual GSI summer party, idylically taking place at a small lake next to the facilities.

After the greetings, a representative of the German Federal Ministry of Education and Research, Andreas Storm, spoke a few words and affirming the importance of FAIR and the funding of the project.

Storm said a lot of nice words, among other things he mentioned that the GSI recently had the honor to name the newly discovered chemical element "Copernicium" after its discoverer. Since unfortunately Copernicus died more than 450 years ago, the actual discovery was done by a group to whose leader Storm referred to as Ms Sigurd Hofmann. Hofmann probably doesn't often get mistaken for being a woman. Storm btw is totally hip and has a twitter account.

The below photo shows the pulling up of the "Richtkranz" to the ceiling (to the tune of Ode to Joy on Saxophone and bass, not bad at all):

And here is the master builder, in the traditional dress of a carpenter, toasting on the future of the building. The ceremony was finished by throwing the glass to the floor.

And if you like ducks, here's a photo from the little lake where we then went and grabbed some cake and sausages.

In looking at his website shouldn’t it read “Andreas Storm auf Zwitschern” . It also seems Storm’s Tweeter account is very active at the moment. This of course should be of no great surprise since you are having a general election in three weeks. so I suspect “viel zwitschern in den nächsten Wochen” :-)

I just thought I’d let you know I’m unable to download any of those brochures you highlighted in the article. When I attempt to it just locks up the system and after a long wait I get an error message. I was just wondering if anyone else experienced similar problems?

The brochures download ok for me, and I am quite a lot more than 50 km away....

Would it be FAIR to say that one of the many objectives of FAIR is to probe quark matter at high values of the baryonic chemical potential [as opposed to LHC, which probes higher temperatures but not so high bcp?]

Thanks, I switched browsers and was able to download the smaller of the two brochures. I think there might be a provider issue as well. Oh yes as I recall Bee once mentioning she hasn’t been able to vote in an election for years and was wondering if she was going to cast a ballot in an advanced poll before departing for Stockholm? It certainly is a strange system you have, where you can vote for a different party then the member you choose. Then again, perhaps it leaves the politicians so at odds with one another and so bogged down with the complexities of their own internal bureaucracy that they have less time to find ways to mess up the electorat's lives; so there may be some logic to it after all:-)

Then again, perhaps it leaves the politicians so at odds with one another and so bogged down with the complexities of their own internal bureaucracy that they have less time to find ways to mess up the electorat's lives; so there may be some logic to it after all:-)

… that one of the many objectives of FAIR is to probe quark matter at high values of the baryonic chemical potential

Exactly – the idea is to produce collisions of uranium ions with √s in the range 10…40 GeV/nucleon, which has not been explored in previous experiments, and where the highest compression and highest net baryon density (corresponding to some positive baryon chemical potential) is expected. The respective detector and experiment is the "Compressed Baryonic Matter (CBM)" Experiment. In this phase diagram of nuclear matter from the CBM website, the expected "trajectories" in the T/μ-plane are shown.

Hi Arun,

In a sense, FAIR is the ultimate realization of the dreams of the ancient alchemists

True! Maybe they should chose some famous alchemist when they name the next element ;-).

I've understood your comment like that- just wasn't sure if some other "strange" German tradition had slipped in unbeknownst to me ;-)

Actually, as someone who has grown up with the tradition of the "Richtfest", I wasn't aware at all that this is something quite specific to Germany, until I've looked up the English translation of the word and read the Wikipedia entry.

I was finally able to download both those brochures and found them very informative yet even more so what you pointed out to Pope. When first exploring the characteristics of what is now called ‘quark soup’ at the RHIC, it was initially thought it would have more gas like (‘plasma’) qualities, yet as it turned out they were more like a ideal liquid, with near zero viscosity. The thing that has always had me to wonder is what phase the Universe was in during its hypothesised inflationary period and what if any implications do these experiments have in such regard?

That is to ask, does running heavy ions into each other at extreme high speed truly have it represent the state of things during the early moments of the universe, since matter/energy then was so confined not due a elevated energy level yet rather resultant of the actual size of the space which existed; whereas here it is brought into such proximity not as being a limitation of physical space in terms of the system. I guess what asking, is it fair to say that such experiments actually do duplicate conditions at such times in as we are only raising matter/energy density and not that of space itself.

Phil asked: "The thing that has always had me to wonder is what phase the Universe was in during its hypothesised inflationary period and what if any implications do these experiments have in such regard? "

Have a look at the phase diagram Stefan pointed out to me. You will see there that the LHC will probe more in the direction of conditions in the early universe [where there were roughly equal numbers of particles and antiparticles]. FAIR goes off into even more mysterious territory, investigating conditions roughly like those in cores of neutron stars [perhaps soon after they form, before they get cold]. [Well, the way they draw it, they will end up in the QGP, which I guess is not really like a neutron star core! But I speculate wildly that they will actually hit *another* phase, like in the phase diagram of water, as discussed here by Stefan long ago......]

The thing that has always had me to wonder is what phase the Universe was in during its hypothesised inflationary period and what if any implications do these experiments have in such regard?

Aeh, well, the quark-gluon phase is quite "late" compared to the inflationary phase - there is electroweak symmetry breaking in between, and possibly GUT and SUSY breaking and all kind of other weird stuff. So, I don't see a connection to the inflationary period.

does running heavy ions into each other at extreme high speed truly have it represent the state of things during the early moments of the universe... such experiments actually do duplicate conditions at such times in as we are only raising matter/energy density and not that of space itself.

Right - there is no "compression" of spacetime involved. The relation of heavy-ion collisions at RHIC and the LHC to the early universe is that the quark-gluon plasma has existed back then, and that this phase of matter is recreated in a very tiny volume for a very short time in the heavy-ion collision. Of course, spacetime in the region of the collision remains perfectly flat Minkowski, there is no shrinking or expansion of spacetime. This is one difference to the early universe, the other is the timescale: the QGP in the early universe was in thermal equilibrium, the expansion of the universe notwithstanding. If and how thermal equilibrium is reached in heavy-ion collisions is less evident. We had discussed these differences in more detail in the post Recreating the Big Bang?

Please note also the difference between heavy-ion collisions at RHIC and LHC, and FAIR, as pointed out by Pope. RHIC and LHC yield higher collision energies than FAIR, and hence, there are much more particle-antiparticle pairs produced. This is described by the "chemical potential" - chemical potential zero meaning equal amounts of particles and antiparticles. The early universe was nearly equal in matter and antimatter, hence, had a very small or even zero chemical potential. In this respect, then, heavy-ion collisions at RHIC and LHC resemble more the situation in the early universe than those at FAIR.

"We want to measure when the quark-gluon plasma behaves like a perfect fluid with zero viscosity, and when it doesn't," says Lauret. "When it doesn't match our calculations, what parameters do we have to change? If we can put everything together, we might have a model that reproduces everything we see in our detector." See:Probing the Perfect Liquid with the STAR Grid

What situations in the universe "actually propel" inflation, and these local events, add up, to the total? Where is it that such correlations can be drawn to the collision processes which are simulated in experimental processes??:)

Thanks for the clarification and explanation. I had forgotten that the quark-gluon soup forms only after inflation from what before was suppose to be a inflaton particle/field, which is hypothesized to be responsible for inflation and account for the homogeneity of what we call the visible universe. Then again I’m lead to wonder what the differences would exist in this highly compacted space-time at the times when the building blocks for matter/energy emerged. Its just when they claim they are duplicating the early stages of the universe I shutter a bit, since the affects of gravity would be much higher and entropy would be extremely low, neither of which are actually reproduced in such experiments or does it look can be in any experiments that would be possible. It could be said in this respect that any theory of quantum gravity will never be able to be fully testable.